How does Ancestry DNA testing work?

1.DNA samples:

There are several ways to get DNA samples from the body. Now, DNA testing labs use two ways to get DNA. Some labs like 23andme analyze the cells from the saliva that you send back in a test tube. Other labs like familytreedna get the DNA from the inside the cheek. They send a sort of tooth brush that you use to scrape the inside of your cheek.

2.Extraction:

When the saliva sample or the cheek sample reaches the lab, the DNA is extracted from the cell.

3.Amplification:

Then, copies of this DNA are made in a special machine to obtain a big amount of material to test.

4.Getting the data:

the DNA is placed on a biochip in a special machine where the temperature is increased. The DNA’s stick to the chips. A laser beam reads the chip data. The DNA is then turned into a raw data file.

5.Storing:

The data is stored on a secured server in a data center.

6. Analysis:

Autosomal DNA test: This test checks 22 chromosomes and compares the results to reference populations like the Native America population. For your information, the choice and the number of reference population change from one DNA testing lab to another. Percentage of ethnicity makeup are calculated from this analysis. This includes heritage from paternal and maternal lineage.

Y DNA test: It is a test about the Y chromosome. Only men have a Y chromosome. This test is for men. The Y DNA test helps to know the origin of the paternal lineage (father of the father of the father…). The result is the haplogroup Y.

mtDNA DNA: This is the analysis of mitochondria which is inherited from the mother. The result is the mtDNA haplogroup. All the children from one mother have the same haplogroup mtDNA.

7.Results of DNA tests:

Comparison between users: DNA segments of a user are compared to segments from other users in the database of the DNA testing website. Identical segments allow calculating the level of parentage among users. In this context, parents and children share roughly 50% of DNA.

Determination of ethnicity makeup: DNA are compared to ethnicity population profiles. If a user has a specific marker, this takes part of the calculation for the percentages of ethnicity makeup.

Determination of maternal lineage: This is the test of mitochondria DNA. mtDNA is inheritated from mothers to children. The result is the mtDNA haplogroup. This does not change that much over the years.

Determination of the paternal lineage: By comparing results from Y DNA analysis of a user and patterns from the main Y haplogroups, a programm determines the Y haplogroup of the male user.

Below you can find the procedure for the different DNA testing labs that we discuss on this website.